Pyro is great and V10 is better. V10 seems to be a bit cleaner. With pyro, you would occasionally (barely ever) get tiny flakes of chalk on the cloth. It's almost as if at times (like a wildly struck miscue) the chalk bunched up. Think of a small tear from hitting a piece of saran wrap on a solid surface with a hammer. It's excellent chalk and played very well but the tip looked odd if you wildly struck it enough to glaze a tip. The tip didn't glaze, but the chalk peeled up. Think of silly putty, it breaks if you pull it too fast.
V10 is basically nothing like that. It plays great and there's no "tearing" or whatever you would call it. Just super consistent coating that is also very clean. No "chalk clouds" like you see on most chalk at break speed. To me, V10 feels more like what you would expect of a classic chalk, but much better grit consistency and it stays on the tip.
The green color isn't an issue on blue cloth because it really doesn't get on there like with other chalks. It's lightning in a bottle as far as I'm concerned regarding chalk. You can do the same thing with a 50 cent cube, but it's much cleaner and much more consistent. One less thing to think about. I won't ever talk badly about Master, it's fine chalk. I have had different batches or different humidity levels in the room make it coat a bit differently. It still worked fine, but again, it's messy.
The only chalk I'll talk bad about is a cube of Sportscraft I tried. That stuff is garbage. Silvercup is OK if you need it to match a cloth color, but it's worse than Master and the same price.